<template>
  <div class="tags" v-if="showTags">
    <ul>
      <li
        class="tags-li"
        v-for="(item, index) in tagsList"
        :class="{ active: isActive(item.path) }"
        :key="index"
      >
        <router-link :to="item.path" class="tags-li-title">
          {{ item.title }}
        </router-link>

        <span class="tags-li-icon" @click="closeTags(index)">
          <i class="el-icon-close"></i>
        </span>
      </li>
    </ul>

    <div class="tags-close-box">
      <el-dropdown @command="handleTags">
        <el-button size="mini" type="warning">
          标签选项

          <i class="el-icon-arrow-down el-icon--right"></i>
        </el-button>

        <el-dropdown-menu size="small" slot="dropdown">
          <el-dropdown-item command="other">关闭其他</el-dropdown-item>

          <el-dropdown-item command="all">关闭所有</el-dropdown-item>
        </el-dropdown-menu>
      </el-dropdown>
    </div>
  </div>
</template>

<script>
import bus from "./bus";

export default {
  data() {
    return {
      tagsList: []
    };
  },

  methods: {
    isActive(path) {
      return path.split("?")[0] === this.$route.fullPath.split("?")[0];
    },

    // 关闭单个标签

    closeTags(index) {
      const delItem = this.tagsList.splice(index, 1)[0];

      const item = this.tagsList[index]
        ? this.tagsList[index]
        : this.tagsList[index - 1];

      if (item) {
        delItem.path === this.$route.fullPath && this.$router.push(item.path);
      } else {
        this.$router.push("/");
      }
    },

    // 关闭全部标签

    closeAll() {
      this.tagsList = [];

      this.$router.push("/");
    },

    // 关闭其他标签

    closeOther() {
      const curItem = this.tagsList.filter(item => {
        return item.path === this.$route.fullPath;
      });

      this.tagsList = curItem;
    },

    // 设置标签

    setTags(route) {
      const isExist = this.tagsList.some(item => {
        return item.path.split("?")[0] === route.fullPath.split("?")[0];
      });

      if (!isExist) {
        if (this.tagsList.length >= 10) {
          this.tagsList.shift();
        }

        this.tagsList.push({
          title: route.meta.title,

          path: route.fullPath,

          name: route.name
        });
      } else {
        const sameArry = this.tagsList.filter(
          item => item.path.split("?")[0] === route.fullPath.split("?")[0]
        );

        const index = this.tagsList.findIndex(item => item === sameArry[0]);

        this.tagsList.splice(index, 1, {
          title: route.meta.title,

          path: route.fullPath,

          name: route.name
        });
      }

      bus.$emit("tags", this.tagsList);
    },

    handleTags(command) {
      command === "other" ? this.closeOther() : this.closeAll();
    }
  },

  computed: {
    showTags() {
      return this.tagsList.length > 0;
    }
  },

  watch: {
    $route(newValue) {
      this.setTags(newValue);
    },

    tagsList(newValue) {
      localStorage.setItem("tags", JSON.stringify(newValue));
    }
  },

  created() {
    this.setTags(this.$route);

    const tagsList = JSON.parse(localStorage.getItem("tags"));

    if (tagsList && tagsList.length) {
      this.tagsList = tagsList;
    }

    // 监听关闭当前页面的标签页

    bus.$on("close_current_tags", () => {
      for (let i = 0, len = this.tagsList.length; i < len; i++) {
        const item = this.tagsList[i];

        if (item.path === this.$route.fullPath) {
          if (i < len - 1) {
            this.$router.push(this.tagsList[i + 1].path);
          } else if (i > 0) {
            this.$router.push(this.tagsList[i - 1].path);
          } else {
            this.$router.push("/");
          }

          this.tagsList.splice(i, 1);

          break;
        }
      }
    });
  }
};
</script>

<style lang="less">
.tags {
  position: relative;
  box-sizing: border-box;
  height: 42px;
  overflow: hidden;
  padding: 5px 120px 0 20px;
}

.tags ul {
  box-sizing: border-box;

  width: 100%;

  height: 100%;
}

.tags-li {
  float: left;

  margin-right: 8px;

  border-radius: 4px;

  font-size: 12px;

  overflow: hidden;

  cursor: pointer;

  height: 32px;

  line-height: 32px;

  border: 1px solid #dddddd;

  background: #fff;

  padding: 0 5px 0 12px;

  vertical-align: middle;

  color: #666;

  -webkit-transition: all 0.3s ease-in;

  -moz-transition: all 0.3s ease-in;

  transition: all 0.3s ease-in;
  box-sizing: border-box;
}

.tags-li:not(.active):hover {
  background: #f8f8f8;
}

.tags-li-title {
  float: left;

  max-width: 80px;

  overflow: hidden;

  white-space: nowrap;

  text-overflow: ellipsis;

  margin-right: 5px;

  color: #666;
}

.tags-close-box {
  position: absolute;

  right: 36px;

  top: 8px;

  box-sizing: border-box;

  text-align: center;

  width: 110px;

  height: 32px;

  z-index: 10;

  .el-button--mini {
    padding: 6px 17px;
  }

  [class*=" el-icon-"],
  [class^="el-icon-"] {
    color: #909399;
  }

  [class*=" el-icon-"]:hover,
  [class^="el-icon-"]:hover {
    color: #fff;

    font-size: 14px;
  }
}
</style>
